#2 Prepare the frame. The picture shows the arms with the sharp corners sanded at a 45 degree angle with some 120grit wet and dry sandpaper under running water. There's no need to go too hard or far, just some sandpaper on a finger to get a smoother round edge. Alternatively this can be skipped, the edges are sharp and the sanding helps prevent splintering/chipping due to impacts. The next step past sanding is coating the edges with CA/Superglue.

The camera plates have not been sanded and the arms have in this picture.

#3 Check the motor alignment and fit. This is where you confirm that the arms are up the right way for the wires from the motor to go where you want them. If they seem to point out at 90 degrees with the bolt holes lined up correctly, flip the arm. After this step the bottom plate, arms and PDB can be bolted together in the correct orientation....Continue Reading